Jumbo Koi

​“Jumbo Koi” has a special sound for the Japanese Koi lovers and we aim to be #1 in Jumbo Koi For sale online!

The definition of “Jumbo Koi” is actually quite vague. It has been misused or overused by many dealers in the industry. At Kodama Koi Farm, we define “Jumbo” as Koi that are at least 60cm or 24 inches long. This page shows our Jumbo koi listed online, scroll down to see Jumbo koi we have available for purchase and info on what qualifies koi as jumbo.

The reason why Koi is called the king of ornamental fish is because of the growth. Some Koi can grow over 1 meter or 40 inches. As Koi grows jumbo, the pattern, the color, the body change. Koi transforms to the very living jewels. Owning jumbo Koi and/or watching the growing process to the jumbo Koi are the real thrill and nothing but pleasure.

“Jumbo Tosai” is a popular term too. It means Tosai or baby Koi (1 year old) that are bigger than the average, thus considered to have potential to grow into a jumbo sized koi. Although it depends on when to measure the size of Tosai, if they are 25cm or 10 inches in April, we believe it is safe to say they are jumbo. Most of our babies are about 4-8” around then. Make sure you are buying from a trusted koi dealer who can help explain more about what is a jumbo koi.

How Large Do Koi Grow? / What Size is Jumbo Koi?

If you are a Koi beginner, you probably imagine their size as 20 inches based on your experience of seeing a Koi in public, but the biggest exhibited Koi will blow your mind and break a Koi-size-record in your head.

In the 38th All Japan Koi Show, a Koi in a size of 97cm (about 38”) won the biggest Koi of the year, and it’s the largest Koi in history so far. Since Nishikigoi are mutated from carp (which have gotten as big as 1.5 m and almost 100lbs) we think we may see koi that are as large as these wild carp one day!

Jumbo koi are any koi over 24" or have potential to grow jumbo. 38" is the largest known koi size, but it is possible more koi will grow bigger in the future and more jumbo koi for sale be available.

How Large is a Jumbo Koi (VIDEO)


Your koi will grow bigger if you use quality food, that has a higher feed efficiency, but may not always turn into a jumbo koi. Feed efficiency is a measurement to determine what percentage of food weight is turned into fish weight. You are what you eat from your head down to your…dorsal fin?

When raising nishikigoi, choosing ingredients carefully is a must. Just because koi enjoy the taste of a food doesn't mean its good for creating jumbo koi! Like human junk food, additives can make a feed tasty, covering up its lack of nutrients with enthusiasm during feeding. Let’s help you get it all: vibrant, healthy champion koi, who are active and fun for you and your family to spend time with.

Read about our best types of koi food guide for increasing color and growth size.

How We Move our Jumbo Koi for Sale

In this video you can see examples of our Jumbo Koi and how big they really are, when we move them from their main pond to their holding pond, preparing these Jumbo Koi for sale.


How We Grow Large Koi

When growing Koi to jumbo size, there are four things to consider: Bloodline, Gender, Food, and Water

1. Bloodline

You can never ignore the genetic reasons for the potential of large Koi. If Koi comes from famous breeders like Dainichi, Isa, Marudo and other breeders we carry, they all should have the genes to grow big. These breeders use very high quality and jumbo Koi as the parents, the offsprings have the gene to grow jumbo like the parents Koi.

2. Gender

In general, females are likely to grow bigger than male. It does not mean male will not grow big, but female, probably they carry eggs, eat more and grow bigger and wider. I do not consider it is an absolute condition, but female is easier and preferred if you want to grow Koi bigger than 24”

3. Food

What to feed and how much to feed is the key. Even if the Koi has the DNA, if it does not have a healthy and proper diet, it will not grow. Please be sure you feed high quality food like Kodama Koi Food. Low end foods has a lot of fillers. They will not help your Koi grow big.

4. Water

Maintaining the healthy environment is also critical. Especially because you are feeding a lot, please make sure your biological cycle works well. Water change is also very important to help your Koi grow big. If you are serious about growing jumbo Koi, 10% daily water change is recommended.

Examples of Sold Jumbo Sized Koi From Kodama Koi Farm

Taisho Sanke - koi #q1203p002

Taisho Sanke

Estimated Value: $15,000.00
Sex: Female
Born in: 2015
Size: 27.56 inch
Ginrin Kohaku - koi #q1203p013

Ginrin Kohaku

Estimated Value: $8,000.00
Sex: Female
Born in: 2016
Size: 24.41 inch
Doitsu Benigoi - koi #q1203p011

Doitsu Benigoi

Estimated Value: $6,000.00
Sex: Female
Born in: 2016
Size: 25.98 inch

Mukashi Ogon

Estimated Value: $10,000.00
Sex: Female
Born in: 2016
Size: 31.1 inch

Pictures of Jumbo Koi from Japan

View our Jumbo Koi For Sale

We are now very happy to offer you our wide selection of genuine Jumbo Koi for sale and baby Jumbo Koi for sale.

We have Jumbo koi available to buy, if shown below the search field. If not, please use request a koi with what you are looking for and we will help find the right koi for you in our farm's offline inventory.

Search All Our Available Koi

Search by breeder

Search by variety

Search by price type

Showing 1–16 of 24 results

Can't find the koi you're looking for? Click here to use our koi request form

Request the Koi of Your Dreams

What can we help you find?

Let us know more about what you are searching for and we will look into our inventory to help you find the perfect koi. Tell us a description, variety, size range, and price range you are searching for.

We have a large stock of koi that are not listed on our website and we can also look when we are visiting Niigata, Japan. Complete this form and we will follow up with you directly.


Koi Request Form